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A government watchdog report has identified a dramatic increase in documented corruption cases among U.S. border and immigration agents, finding nearly 150 have been arrested or indicted since 2005.

In a trend one top lawmaker said puts national security "in jeopardy," the Government Accountability Office tracked the rise in corruption cases among Border Patrol, Customs and Border Protection, and Immigration and Customs Enforcement agents. The report, issued last month, found spotty standards in screening new applicants and keeping tabs on agents after they're hired.

It found the trend was tied in part to the demand to beef up security, particularly along the southwest border, by hiring more agents, and has raised red flags in Congress.

"Just one employee collaborating with a drug smuggler or terrorist can put our entire nation at risk," said Rep. Michael McCaul, R-Texas, chairman of the House Committee on Homeland Security.

McCaul, who along with Sen. Tom Coburn, R-Okla., requested the report, said one problem is that while the CBP now polygraphs all new hires, it does not follow up and test employees after they join.

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"The GAO report confirms that not only is corruption still a problem, CBP still lacks adequate controls to detect corruption, such as post-employment polygraphing," McCaul told FoxNews.com, adding that one CBP official has said that among those who become corrupt, the behavior sets in roughly 8.8 years into service.

According to the GAO's findings, since 2005, 2,170 agents have been arrested for non-corruption charges such as domestic violence and driving while intoxicated. However, 144 were arrested or indicted for direct corruption-related activities such as drug and human smuggling. By Oct. 2012, 125 of these agents had been convicted.

While the GAO downplayed the matter by noting the cases only represented less than 1 percent of the entire agency, a May 2012 article by the Center for Investigative Reporting showed that between 2006 and 2010 the number of corruption cases being investigated jumped from 244 to 870.

"In fiscal year 2011 alone, the DHS Inspector General received almost 900 allegations of corruption from within CBP and ICE," McCaul said.

McCaul has long asserted the presence of Islamic extremists groups such as Hezbollah -- which has been found to be working in collaboration with Mexican cartels -- coupled with the prospect of a corrupt officer intentionally allowing these individuals into the U.S. could be catastrophic.

The crux of the GAO's report found that the CBP was unable to handle the rapid demand for agents and that there was a disconnect between supervisors and the agency's Office of Internal Affairs, which did not  maintain or track information obtained from background checks, drug tests or polygraphs.

The agency has also failed to consistently conduct monthly quality assurance reviews of its adjudications since 2008, hampering efforts to prevent future incidents of corruption. A culture of resisting the efforts of the Office of Internal Affairs was also uncovered.

The GAO report said that Department of Homeland Security officials have testified that CBP's increased hiring of officers and agents since fiscal year 2006 likewise increased the opportunities for attempted corruption.

Between 2006 and August 2012, more than 17,000 new agents were hired, the majority of whom were stationed along the U.S.-Mexico border.

There is speculation that some applicants may have applied to work for CBP with pre-existing ties to drug cartels facilitating drug trafficking.

In 2010, the CBP assistant commissioner for internal affairs told the homeland security subcommittee that only one in 10 applicants was even polygraphed during the rush to hire new agents. Of this group, some 60 percent were deemed unsuitable for hiring.

This prompted the passage of the Anti-Border Corruption Act of 2010 which requires that by January 2013, all applicants be polygraphed before hiring.

With an estimated $40 billion in drugs crossing the U.S.-Mexico border annually, the battle against temptation is daunting.

In 2005, agent Juan Alfredo Alvarez accepted some $1.5 million to let trucks loaded with more than a ton of marijuana through checkpoints in southeast Texas.

Raul and Fidel Villareal were arrested in Tijuana after being charged with smuggling hundreds of undocumented immigrants through the San Ysidro area of California.

In 2011, Abel Canales accepted $8,000 to allow drug shipments to pass from Mexico into the U.S. through Arizona.
Solomon Ruiz was sentenced to 14 years in prison after he was caught directing drug shipments into the U.S. Ruiz asked for a $10,000 retainer fee and said that he charged $4,000 to escort a car and $6,000 to escort a van.

"We must ensure that DHS commits to an effective integrity strategy as part of a comprehensive strategy to secure our borders," McCaul said. "Until the department addresses its own Internal Affairs failures and implements clear ethical standards, our national security will be in jeopardy."

A CBP representative said the agency would follow the GAO report's recommendations.

"CBP agrees with the seven recommendations the GAO report on CBP's workforce integrity has identified and will implement appropriate measures to address all of them including the feasibility of expanding the polygraph program to incumbent law enforcement officers, developing a plan to implement a comprehensive integrity strategy, and completing post-corruption analysis reports for all CBP employees who have been convicted of corruption-related activities to help identify and prevent future corruption and misconduct risks," CBP spokeswoman Joanne Ferreira said.